Question: Last Monday, Ben's parents gave birth to twins and named them Gabriela and Daniel. When they were first born, Gabriela weighed 8.64 pounds and was 20.5 inches tall, and Daniel weighed 9.19 pounds and was 21.5 inches tall. How much did the babies weigh in total?
Solution: To find the weights of the 2 babies, we need to add their weights together. Gabriela's weight + Daniel's weight = total weight. ${8}$ ${6}$ ${4}$ ${9}$ ${1}$ ${9}$ ${+\vphantom{0}}$ ${3}$ ${8}$ ${7}$ ${1}$ Together, the babies weigh 17.83 pounds.